Packing for throttle-valve stems.



PATENTED NOV. 1, 1904.

S. LOGKHART.

PACKING FOR THROTTLE VALVE STEMS.

APPLICATION FILED JUNE 22, 1904.

N0 MODEL.

WITNESSES UNITED STATES Patented November 1, 1904.

SAMUEL LOCKHART. OF PITTSBURG, PENNSYLVANIA.

PACKING FOR THROTTLE-VALVE STEIVIS.

SPECIFICATION forming part of Letters Patent No. 773,949, dated November 1, 1904.

Application filer- June 22, 1904. Serial No. 213,603. (No model.)

To all whom it may concern.-

Be it known that I, SAMUEL LOOKHART, a resident of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Packings for Throttle-Valve Stems; and I do hereby declare thefollowing to be a full, clear, and exact description thereof.

My invention relates to packings for throttle-valves, and has special reference to such packings as are used in the packing of locomotive throttle-valve stems and other like steam-valve stems.

The object of my invention is to provide a cheap, simple, and eifective packing for such purposes and uses, as well as one which will not become worn by friction or burn out and will reduce leakage to a great extent.

A further object is to produce such a packing which can be easily and quickly placed around the stem, as well as one which can be made and handled as a single piece or article.

My invention consists, generally stated, in the novel composition, arrangement, construction, and combination of parts, as hereinafter more specifically set forth and described, and particularly pointed out in the claims.

To enable others skilled in the art to which my invention appertains to make and use my improved packing for throttle valves, I will describe the same more fully, referring to the accompanying drawings, in whicl Figure 1 is a longitudinal section ofathrottle-valve stufling-box, showing my improved packing applied therein. Fig. 2 is aside view of said packing. Fig. 3 is an end view of the same. Fig. 4 is a longitudinal section of the same. Fig. 5 is a cross-section thereof, and Figs. 6 and 7 are sections of another form of the same.

Like symbols of reference herein indicate like parts in each of the figures of the drawings.

As illustrated in the drawings, 1 represents the stuffing-box of the ordinary throttle-valve, and 2 the throttle-stem passing through the same, to which the throttle (not shown) is connected in the usual manner for operating the same. WVithin the stuffing-box 1 is the usual packing-cavity 3, which extends around the stem 2 and is provided with the inclined end faces L a, formed on the follower-gland 5 and inner gland 5, respectively, suchinner gland being secured within the boiler a in the ordinary manner, and the follower-gland is removably bolted thereto by the bolts 5'.

My improved packing 6 is of tubular shape and is made of hard rubber, although graphite or soapstone can be used to form the same, and such packing is banded or formed together from the proper amounts or proportions of these ingredients or materials around a mandrel or other suitable device and by any suitable treating or mixing for uniting or banding the same together which will form the body portion 6, the beveled ends 6, and the opening or interior cavity 7 through the same. If desired, a thin lining of graphite, such as is shown at 8, can be formed within the interior cavity 7, and canvas, cotton duck, or other suitable fabric 9 can be placed around and throughout a portion of the length of the body portion 5, as shown in Figs. 6 and 7 My improved packing being thus made in a solid form can be placed within the cavity 3 of the stuffing-box 1 by any suitable means and in any suitable manner and when in place conforms to said cavity Sin shape and size, so that the beveled orinclined ends 6 on said packing fit against like inclined faces 4 L in said cavity and on the glands 5 and 5, While the opening 7 through the said packing is of the same size and fits around the stem 2 by its lining 8 when used.

It will be evident that by reason of my improved packing'being made in solid form that the same can be easily and quickly placed within the packing-cavities when desired and that if necessary the same can be split longitudinally or vertically for the purpose of passing and covering any projections within the packing-cavity or upon the stem. It will also be evident that practical experience in the use of my improved packing for throttlevalves in connection with locomotives has proven that it will last longer than the'ordinary packing now used for like purposes and will overcome the friction in the stem to a very large extent. The packing can be easily and cheaply manufactured, will not burn out,

and does not require any pressure on the same to form a packed joint or be used in any manner but its original shape, while at the same time such a packing is strong and durable and does not require any further attention when once in place. By the fabric not reaching the extreme ends of the packing all liability of the packing becoming injured by steam or water is overcome and the packing will still retain its strength by such fabric.

What I claim, broadly, as my invention, and desire to secure by Letters Patent, is-

1. As a new article of manufacture, a pack ing for throttle-valve stems formed of a solid rubber tube, the interior diameter of which is of the same size as the exterior diameter of the stern and the exterior diameter of which is of the same size as the diameter of the packingcavity, said tube having beveled ends thereon for fitting against like end faces in said cavity and a thin lining of graphite on interior surface of said tube.

2. As a new article of manufacture, a packing for throttle-valve stems formed of a solid rubber tube, the interior diameter of which is of the same size as the exterior diameter of the stem and the exterior diameter of which is of the same size as the diameter of the packing-cavity, said. tube having beveled ends for fitting against like end faces in said cavity, and a suitable fabric extending around and through the body of said tube.

3. As a new article of manufacture, a paclu SAMUEL LOCKI-IART.

\Vitnesses:

J. N. (100103, ROBERT I-I. AxTHuLM. 

